This disclosure generally relates to heat transfer devices, in particular to thermoelectric devices and modules for transferring heat from a heat source to a heat sink. More particularly, this disclosure relates to thermoelectric devices that can be coupled to objects to be heated or cooled.
Thermoelectric devices for cooling are used to transfer excess heat from electronic devices, such as sensors, active electro-optical components, infrared CCD chips and the like. As many electronic devices have low power dissipation, additional cooling means are desired. Electric cooling was first discovered by John Charles Peltier who observed that a current flowing through a junction between dissimilar conductors, such as n- or p-type semiconductors, can induce heat or cooling as a function of the current flow through the junction. This effect is called the Peltier or thermoelectric effect, in which temperature can be increased or lowered depending on the current direction through the junction.
Thermoelectric devices are often used as heat pumps placed between a heat source and a heat sink wherein the heat source can be an electric component and the heat sink sometimes is a surface plate or a convection heat sink. Conventional thermoelectric cooling devices often use multiple stages to stepwise cool down an object or transfer heat away from a heat source. Such multi-stage modules essentially consist of separate thermoelectric modules stacked on top of each other. This leads to additional space requirements and an increase in expenditure due to the plurality and complexity of thermoelectric components involved. It is generally desirable, however, to increase the efficiency of thermoelectric cooling modules.